Traditionally, air bag tethers have been used to control the excursion of an air bag as it inflates. As gas is released, causing the air bag to rapidly inflate, it is necessary to keep such inflation from occurring in an uncontrolled manner. Tethers, which are sewn to the front and rear panels of an air bag, keep the inflating air bag from expanding so rapidly as to adversely affect the safety of the vehicle occupant, as the vehicle occupant contacts the air bag.
Tethers are conventionally strip-shaped pieces of fabric that are aligned in pattern-wise arrangement on a fabric blank, or that are aligned in relation to air bag panels that may be cut from the same blank. The patterns for these tethers may include a circular portion in the center area of the tether strip around which the strip is attached to the air bag panel. It is understood in the industry that such tethers should have a capacity for elongation (that is, the tethers should be able to stretch to accommodate the rapid excursion of the bag). For this reason, conventional tethers have been cut on the bias with respect to the warp and fill of the fabric. However, aligning the tether patterns to meet this criterion increases the amount of fabric needed to create an appropriate number of tethers for a plurality of air bags. Furthermore, because fabric utilization comprises more than fifty percent of the costs of a finished air bag, aligning the tethers in this manner increases production costs.